• Molarity, Basic

A solution is prepared by dissolving 17.2 g of ethylene glycol (C2H6O2) in 0.500 kg of water.  The final volume of the solution is 515 mL. For this solution, calculate the concentration in molarity. 

• Molarity, Ions in solution

Which of the following solutions contains the greatest number of ions? (Multiple choice)

• • 1. 400.0 mL of 0.10 M NaCl

    2. 300.0 mL of 0.10 M CaCl2

    3. 200.0 mL of 0.10 M FeCl3

    4. 800.0 mL of 0.10 M sucrose

• Writing equations for precipitation reactions

Part 1:

Write the molecular, complete and net ionic equations for the precipitation reaction that occurs (if any) when solutions of potassium carbonate and nickel (II) chloride are mixed.

Part 2: 

Write the molecular, complete and net ionic equations for the precipitation reaction that occurs (if any) when solutions of sodium nitrate and lithium sulfate are mixed. 

• Stoichiometry of precipitation reactions

Calculate the mass of solid NaCl that must be added to 1.50 L of a 0.100 M AgNO3 solution to precipitate all the Ag+ ions in the form of AgCl. 

• Assigning Oxidation States

Assign an oxidation state to each atom in each element, ion, or compound. 

    (a)  Cl2               (b) Na+                (c) KF               (d) CO2                (e) SO42-               (f) K2O2

• Using Oxidation States to Identify Oxidation and Reduction 

Use oxidation states to identify the element that is oxidized and the element that is reduced in the following redox reaction:

Mg (s) + 2 H2O (l)  →  Mg(OH)2 (aq) + H2 (g)

• Balance Redox: Half-Reaction Method in Acidic Solution

Balance the redox equation in an acidic environment:

Fe2+ + MnO4- → Fe3+ + Mn2+ 

• Balance Redox: Half-Reaction Method in Basic Solution

Balance the equation occurring in basic solution:

I- (aq)  + MnO4 (aq)  →  I2 (aq) + MnO2 (s)

• Stoichiometry

Sulfuric acid (H2SO4) is a component of acid rain that forms when SO2, a pollutant, reacts with oxygen and water according to the simplified reaction:

2 SO2 (g) + O2 (g) + 2 H2O (l) → 2 H2SO4 (aq)

The generation of the electricity used by a medium-sized home produces about 25 kg of SO2 per year. Assuming that there is more than enough O2 and H2O, what mass of H2SO4, in kg, can form from this much SO2?

• Stoichiometry, Limiting Reactant

Consider the following reaction of methane with chlorine gas to make carbon tetrachloride and hydrogen chloride.

CH4 + 4Cl2 → CCl4 + 4 HCl

How many grams of HCl will be produced when 97.2 g of chlorine gas is allowed to completely react with 7.25 g of methane gas?

• Stoichiometry, Excess Left Over

The reaction below is one method of creating nitric acid from nitrogen dioxide and water:

3 NO2  +  H2O  →  2 HNO3  +  NO

When 138 g of nitrogen dioxide reacts with 54.0g of water, 126 g of nitric acid is formed.  From these quantities, nitrogen dioxide is the limiting reactant. How many grams of water is left over when the reaction goes to completion?

• Limiting Reactant and Theoretical Yield

The reaction of 7.8 g of benzene, C6H6, with excess nitric acid resulted in 0.90 g of H2O.  What is the percent yield of this reaction?

C6H6  +  HNO3  →  C6H5NO2  +  H2O